Air chuck



Patented Feb. 9, 1937 UNITED STATES PATENT OFFICE AIR CHUCK Application December 21, 1934, Serial No. 758,676

11 Claims.

This invention relates to improvements in air chucks such as are commonly employed for ccnnecting a source of pressure fluid with a container for receiving it, and this includes delivery from an initial source to a container, or from a container to a gauge; and more specifically the invention relates to coupling devices of the type employed on pneumatic tire gauges and air pressure lines.

1t has been commonly proposed heretofore to provide in such coupling device a body having the requisite chambers and passageway, a valve therein, and an elastic seat for the valve marginally clamped in the body and adapted to be flexed during operation, but such elastic valve seats have been found in use to harden somewhat along the areas where the material is clamped or distorted by the gripping action which is depended upon to retain the seat in its place and to otherwise deteriorate and require replacement at comparatively frequent intervals. It is an object of the present invention to completely obviate such tendency toward deterioration by avoiding any clamping or gripping action.

A further object is the increasing of the cushioning action of the elastic seat for the valve of an air chuck.

With these and further objects in view as will in part hereinafter become apparent and in part be stated, the invention includes the provision of an elastic valve seat in an air chuck combination which is itself air cushioned.

The invention also includes in such a structure provision for free movement of the elastic seat for affording maximum advantage of the cushioning action.

The invention also includes certain other novel constructions, combinations, and arrangements of parts as subsequently specified and claimed.

In the accompanying drawing,-

Figure 1 is a view in central, Vertical section through an air chuck embodying the features of the present invention, parts being seen in elevation, and a portion of the hose or gauge connection being broken away.

Figure 2 is a view similar to Figure 1 with the parts in the position when connection is made to the valve stem.

Figure 3 is a plan view thereof, the hose or gauge connection being omitted.

Figure 4 is a detailed, edge View of the valve detached, the view being taken at right angles to the plane of the section of Figures 1 and 2.

Figures 5 and 6 are views similar respectively to Figures 1 and 2 of a somewhat modified embodiment.

Referring to the drawing by numerals, I indicates the body of an air chuck which may have any appropriate connections 2 to an air gauge or supply hose, the connections 2 in the specific embodiment shown including a threaded engagement 3 whereby the chuck body I can be quickly and readily attached to and detached from the part with which it is connected during use.

The body I is formed interiorly with a valve chamber 4, a guiding recess 5 opening into the valve chamber, and a discharge 0r intake port 6 varranged to communicate with the inner extremity of the chamber 4 so as to discharge inward of the valve in said chamber hereinafter described. An outwardly-flared or inwardly tapering passageway 'I leads from the chamber 4 to the exterior of the body I, and the body is preferably formed with a reduced threaded extension 8 forming the material through which the outer portion of the passageway 'I extends.

Arranged within the passageway I is a conical, preferably elastic, gasket 9 conforming in contour to the passageway 'I and of suiciently less diameter to leave a surrounding air jacket space IE] when the gasket 9 is in its outermost position relative to the passageway 'I. The gasket 9 is preferably truncated so as to present a flat end inward, and is proportioned to extend to or approximately to the valve chamber 4 so as to provide and serve as a valve seat for the valve II arranged in the chamber 4. The valve II is preferably a disc having a guiding projection I2 extending loosely into the recess 5 so that the valve I-I can readily reciprocate within the chamber 4 without appreciably canting or becoming otherwise dislocated. A stem I3 outstands from the opposite face of valve II from the projection I2 andis accommodated by a passageway or bore I4 extending axially through the gasket or packing` 9; The passageway I4 is sufciently larger than the stem I3 to permit free passage of air along the stem, and the stem is preferably flattened, as seen in the drawing, to further facilitate such passage. The outer or free end of the stem I3 is tapered at I5 to facilitate location of a valve stem thereagainst and the stem I3 may be provided with an enlargement or head I6 to enable the provision of the taper I5 while leaving a substantial portion flat or blunt at the extreme end of the stem I3. As seen in Figures Band 6, this desirable tapering of the stem can be provided without the employment of an enlargement or head I6 where the stem itself is of sufcient width for that purpose.

The gasket 3 is loosely mounted in the passageway 1 and to retain the gasket against escape from the head I, a cap is provided for the head consisting preferably of a nut I1 threaded onto the threaded portion 8 of the head I and seated against a gasket I8 surrounding the eX- tension 8 and resting against the resulting shoulder of head I at the place from which the extension 8 extends. The engagement of the gasket I8 by nut I1 provides two distinct advantages, one being assurance against leakage of air that may find its way past the threads of the nut and the extension 8, and the other being that the engagement of the nut I1 with the gasket I8 prevents any tendency toward loosening of the nut under ordinary conditions of use. In other words, there is some-what of a gripping action, and, therefore, a resistance or drag between the gasket I8 and the engaged face of nut I1, when the nut is rotated for unscrewing it after it has been seated against the gasket. The gasket I8 may assume any of various shapes, but it is preferably, as seen in the drawing, of such angular form that the beveled portion I 9 of the skirt of nut I1 will snugly fit the exposed face of the gasket. The nut I1 is apertured at 20, and the free end portion of the stem I3 extends into and part way through the aperture. The stem preferably does not extend beyond the nut to prevent injury to the stem during use and rough handling. The aperture 23 preferably includes a beveled or tapering counterbore at its outer extremity to aid in guiding a valve stem into proper engagement with the parts.

As seen in Figure 2, the chuck in operation is preferably applied to a valve stem by being pressed down over the stem, and, as seen in this figure, 2l indicates the valve stern and 22 the rod or plunger of the valve insides. The chuck in being applied over a valve stem in this manner causes the valve stem rst to strike the inclined edges I5 of stem I3 and press back the valve Il, but practically similarly therewith the stem 2l also strikes the exposed portions of the gasket or valve seat 9 and forms an air-tight connection therewith, the parts meanwhile being moved bodily inward within the areas of the chuck body I. The gasket S moves bodily until the air jacket III is eliminated and the gasket reaches an air-tight contact with the surrounding Wall of the passageway 1, and meanwhile the valve II is pushed off of its air-tight seat against the inner end of the gasket 9 so that air can flow either from the valve stem 2| into the valve chamber Il and out through the passageway 6 if the connection 2 is with a valve gauge, or if the said connection is with a compressed air supply hose the air can flow therefrom through the port E, chamber 4, and passageway I4 to the interior of the valve stem 2l. It will be readily understood that meanwhile the rod or plunger 22 has been pressed back by engagement with the blunt, free end of the stem I3, so that the check valve of stem 2| is oft` of its seat. It should be understood that the operation of unseating the valve II, unseating the valve of stem 2l, and seating the gasket 9 against the surrounding walls of passageway 'I is practically an instantaneous operation accomplished by the mere application of the chuck to the valve stern. When the transfer of compressed air, whether from or to the valve stem, is completed, the chuck is merely removed from the valve stem and the connections of the parts that follow is automatic.

The check valve of stem ZI functions to prevent further escape of air, and the valve II is forced to its seat by pressure of air entering through port 6 and in engaging the gasket 9 reseats the gasket against the inner face of the nut I1 so that an air-tight joint is formed between the valve II and gasket 9 and between the gasket 9 and nut I1, and the air jacket Il) is re-established.

Thus, a highly cushioned condition for the parts is established and maintained, and a dependable, non-leaking communication provided for the valve stem 2i and, at the saine time, the gasket 9 is not subjected to the injurious effect of gripping or clamping action of marginal gripping means.

In Figures 5 and 6 is seen a slightly modified embodiment with a hose connection 23 for the chuck .body 23, but the connection 23 may be the same as that above shown and described. A port 25 corresponding to the port 3 is provided and communicates with a valve chamber 23 corresponding to chamber Ll. A valve 21 is arranged in said chamber and provided with a guiding extension 28 reciprocal in and relative to a recess 29 in the body 2li. A stem 3E) outstands from valve 21 and is provided with a beveled outer end portion 3! corresponding to the tapered portion I5. A nut 32 having a passageway 33 corresponding to the nut I1 and passageway 20 is threaded onto a threaded extension of body 24 and seated against a gasket 343 corresponding to the gasket I8. The passageway from the valve chamber 26 to the nut 32 however is slightly different from the pasageway 1 in that a preferably greater inclination or flare is given to a portion of its wall 35, and the balance of the wall is left substantially cylindrical, as seen at 36. A gasket 31 corresponding generally with the gasket 9 is located in the said passageway and has air-tight, face contact with the inner face of nut 32, when the parts are not in operation. The exterior contour of the gasket 31 does not conform with the contour of the wall of the passageway 35, 36, but the gasket preferably has a more abrupt inclined portion 38 than the inclined portion 35 so as to leave an air jacket about the gasket when not in operation in engagement with a valve stern. The portions of the gasket 31 outward of the inclined or conical wall 38 are preferably rounded at 39, 39, so as to avoid abrupt angles and so as to leave the gasket free to rock on the resulting rounded outer portion. The inner extremity of the gasket 31 beyond the conical portion 3B is preferably formed into a substantially cylindrical extension which is preferably slightly smaller in diameter than the diameter of the engaged portion of valve chamber 26 so as to allow air to nd its way into the air jacket space between the inclined walls 35 and 38. Thus, the gasket 34 serves to prevent leakage of air that might nd its way past the threads of the engagement of nut 32 with body 24. The gasket 39 is provided with a central passageway or bore 4I to accommodate the stem 30 and leave sufcient space for the passage of air.

In operation, the structure seen in Figures 5 and 6 functions as indicated in Figure 6, wherein the valve stem 2l is shown as introduced through the opening 33 of nut 32 into engagement With the outer face of the gasket 31. This is accomplished merely by pressing the air chuck down onto the valve stem with the result that the gasket 31 is rocked from the position seen in 75 Figure 5 to the position seen in Figure 6, and is thereby caused to have its conical portion seated snugly against the conical wall of the passageway to prevent leakage therebetween during application to the Valve stem 2l. The operation is otherwise the same as above described, and, when the chuck is removed from the valve stem, the elasticity of the gasket 31 plus the action of the air in chamber 26 in reseating the valve 21 against the gasket 31 restore the parts from the position seen in Figure 6 to the position seen in Figure 5.

The gasket 9 and 31 are preferably of rubber or'other appropriate elastic material to function as above indicated.

What is claimed is:-

1. In an air chuck, the combination, with a body having a valve chamber and pasageway leading therefrom, the walls of which are constructed to form a gasket seat, of a valve in said chamber, a gasket loosely mounted in the passageway, and means for retaining the gasket in said passageway, the construction and arrangement being such that when in one position the gasket is in sealing relation to and co-acting with the valve and the retaining means to prevent leakage and upon application to a valve stem said gasket is moved bodily into sealing relation to and co-aoting with the gasket seat in the passageway to prevent leakage.

2. The combination as claimed in claim l wherein the passageway is tapering and the gasket is also tapering.

3. The combination as claimed in claim 1 with means fcr retaining the gasket against escape from said passageway, the gasket being proportioned to be bodily moved relative to said retaining means when the chuck is applied for ination to a seated position against the walls of said passageway.

e. The combination as claimed in claim 1 wherein the retaining means is a nut having threaded engagement with said body and overhanging the passageway to form a seat for the gasket and limit bodily movement of the gasket whereby to preclude escape of the gasket therefrom.

5. The combination as claimed in claim 1 wherein the retaining means is a nut threaded to said body and having a portion overhanging the passageway to intercept escape of the gasket therefrom and lagainst which the gasket is compressed to normally seal against leakage of air,

and a second means for preventing escape of air leaking past the threaded connection.

6. The combination as claimed in claim 1 with a threaded extension on the body, a nut threaded into engagement therewith and overhanging a portion of the passageway to intercept escape of the gasket therefrom, and a gasket surrounding said extension in position for being engaged by said nut, the skirt of the nut being beveled to enclose the gasket and being seated in engagement therewith.

7. The combination as claimed n claim 1 wherein the passageway is flared outward and the gasket is tapered inwar-d and proportioned to be seated against the walls of the passageway only when the outer terrnnus of the gasket is inward of the outer terminus of the passageway.

8. The combination as claimed in claim 1 wherein the passageway is formed with an inclined wall 4and the gasket is formed also with an inclined wall of a different inclination than the inclination of the passageway to provide a space therebetween, and the gasket is adapted to be moved for seating its inclined wall against the inclined wall of the passageway.

9. The combination as claimed in claim 1 wherein the passageway is formed with an inclined wall and the gasket is formed also with an inclined wall of a different inclination than the inclination of the passageway to provide a space therebetween, an-d the gasket is adapted to be moved for seating its inclined Wall against the inclined wall of the passageway, the gasket having a substantiallycylindrical extension projecting from its inclined portion toward the valve chamber.

10. The combination as claimed in claim 1 wherein the passageway is formed with an inclined wall and the gasket is formed also with an inclined wall of a different inclination than the inclination of the passageway to provide a space therebetween, and the gasket is adapted to be moved for seating its inclined wall against the inclined wall of the passageway, and the gasket having a rounded portion beyond the incline-d wall for facilitating rocking of the gasket to and from a seated position of its inclined wall.

11. The combination as claimed in claim 1 wherein the gasket is free from compression of any kind while the chuck is not being applied for transmission of fluid under pressure.

WALTER H. LONGS'I'REET. 

